Designated Substances ("Dangerous Drugs") Fall Outside Article 24, Item 4(chi): Where the Provision Stops and What Risk Remains

Cases involving what are popularly called dangerous drugs, or in legal terms designated substances (指定薬物), fit the statutory scheme differently from cannabis or stimulant cases when viewed through the lens of a foreign national's residence. The short answer is that designated substances are not among the laws listed in Article 24, item 4(chi) of the Immigration Control and Refugee Recognition Act (入管法). That does not mean there is no effect on your status of residence (在留資格); it means the effect travels by a different route. Knowing exactly where the provision stops and where the risk begins has real practical value when deciding how to approach a case.

Key points

• Designated substances are regulated by the Pharmaceuticals and Medical Devices Act (医薬品医療機器等法), not by the Narcotics and Psychotropics Control Act or the Stimulants Control Act, and so fall outside the laws listed in Article 24, item 4(chi) of the Immigration Act.
• Simple possession, purchase, acquisition and use carry, under Article 84, item 28 of that Act, imprisonment (拘禁刑) of up to three years or a fine of up to 3 million yen, or both.
• If an unsuspended sentence exceeds one year, a ground for deportation (退去強制) under Article 24, item 4(ri) of the Immigration Act arises separately.
• In the examination of an application to extend or change your period of stay, the record will naturally weigh against you when conduct is assessed.
• Depending on how the substance is identified on analysis, a case may instead be charged as a narcotic under the Narcotics and Psychotropics Control Act, moving it onto the ground covered by item 4(chi).

Which law actually regulates designated substances?

The Pharmaceuticals and Medical Devices Act, whose full title is the Act on Securing Quality, Efficacy and Safety of Products Including Pharmaceuticals and Medical Devices. Article 76-4 of that Act prohibits manufacturing, importing, selling, providing, possessing, purchasing, acquiring and using designated substances for purposes other than medical and comparable uses.

The penalties differ according to the conduct. Simple possession, purchase, acquisition and use carry, under Article 84, item 28, imprisonment of up to three years or a fine of up to 3 million yen, or both. Manufacturing, importing or selling as a business carries, under Article 83-9, imprisonment of up to five years or a fine of up to 5 million yen, or both.

Cannabis, by contrast, has since 12 December 2024 been regulated as a narcotic under the Narcotics and Psychotropics Control Act (麻薬及び向精神薬取締法), simple possession carrying imprisonment of up to seven years under Article 66, paragraph 1. Possession, transfer and acquisition of stimulants carry imprisonment of up to ten years under Article 41-2, paragraph 1 of the Stimulants Control Act (覚醒剤取締法). Compared with these, the statutory penalties for designated substances are set at a relatively lower level.

Why does Article 24, item 4(chi) not apply?

Because that item sets out an exhaustive list of the laws it covers. Article 24, item 4(chi) of the Immigration Act names six: the Narcotics and Psychotropics Control Act, the Cannabis Cultivation Control Act (大麻草の栽培の規制に関する法律), the Opium Act (あへん法), the Stimulants Control Act, the Anti-Drug Special Provisions Act (麻薬特例法), and Chapter XIV of Part II of the Penal Code, which covers offences relating to opium smoking.

The Pharmaceuticals and Medical Devices Act appears nowhere on that list. A conviction for an offence involving designated substances therefore does not, by itself, bring you within item 4(chi). For the six listed laws, a harsh rule operates: the mere fact of a guilty verdict creates a ground for deportation, and the outcome is the same whether the sentence was a fine or was suspended. The difference is not a small one.

Does that mean my residence in Japan is safe?

No, that conclusion cannot be drawn. Two other routes of impact remain.

The first is Article 24, item 4(ri). That item makes a person sentenced to life imprisonment, or to imprisonment exceeding one year, deportable. Excluded, however, are those whose sentence has been suspended in its entirety, and those given a partially suspended sentence where the unsuspended portion is one year or less. Cases involving designated substances rarely attract an unsuspended sentence exceeding one year, but the issue can become real where the charge is joined with other offences.

The second is the examination carried out when you apply to extend or change your period of stay. Statuses of residence under Appendix I (別表第一) are granted for a limited period, and each renewal brings a fresh examination. Good conduct is required, and a record of drug-related disposals can be weighed against you. Even where no ground for deportation exists, a refusal to renew means the basis of your residence disappears when the current period expires. Cases involving designated substances are precisely the type that tend to fall into this second route.

Laboratory analysis can change the conclusion

How the seized material is identified can shift which law applies altogether.

If a product sold as a dangerous drug turns out on analysis to contain a substance designated as a narcotic, the case becomes one under the Narcotics and Psychotropics Control Act rather than the Pharmaceuticals and Medical Devices Act. Article 24, item 4(chi) then operates from the moment a guilty verdict is entered. Conversely, if the substance is no more than a designated substance, the case stays outside the list in item 4(chi).

Why we place a decision not to prosecute above everything else

Since the fact of a guilty verdict can, for a foreign national, convert itself into a problem about residence, we take the view that the objective of the defence should be to secure a decision not to prosecute (不起訴処分) before charges are brought.

For a Japanese client, obtaining a suspended sentence at trial can be a wholly satisfactory result. In drug cases, however, Article 24, item 4(chi) carries no proviso, so for a foreign client that outcome is not the finishing line. Even in a designated substance case the position is comparable, because the route through the conduct assessment at renewal remains open. Situations do arise in which a strategy built without regard to the immigration framework produces a moderate criminal outcome yet costs the client the right to remain.

Before charges are laid, the work centres on presenting to the prosecutor who will decide the disposal a clear picture of whether the alleged facts are made out at all, the lawfulness of the seizure, the absence of habitual use, the client's employment and living arrangements, and concrete measures in place to prevent recurrence.

How our office works

Funado International Law Office is at 3F Fuse Building Main Wing, 3-4-10 Takada, Toshima-ku, Tokyo. Attorney Daisuke Matsumura personally handles every stage, from the first detention-centre visit through to the close of trial, and the work is not delegated to clerical staff or junior lawyers.

For Chinese, a dedicated interpreter experienced in cases involving foreign nationals is on staff. Separate from the interpreter appointed by the investigating authorities, you can use an interpreter who stands on your side throughout the criminal process. For English, Vietnamese, Korean and other languages, we arrange an interpreter to suit the particular case.

From cases we have handled

In one case, a woman in her twenties alleged to have acted as a cash collector in a specialised fraud operation obtained a decision not to prosecute after we argued the subjective circumstances in the round (B-1). The careful work of proving what a person actually understood carries over directly into drug and designated substance cases.

In another, a client re-arrested several times as a courier in a specialised fraud operation obtained a decision not to prosecute on every count, achieved through the handling of interrogations, protests against improper questioning, and the steady accumulation of argument and evidence (B-2).

Cases involving designated substances lie outside the reach of Article 24, item 4(chi) of the Immigration Act. That single point gives you solid ground to stand on when planning a case. Even so, item 4(ri) and the renewal examination remain as separate routes, and the identification of the substance may move the case onto entirely different terrain. Rather than assuming the best or the worst, we suggest starting by establishing which law actually applies. This article is a general explanation. For your own situation, please consult a lawyer directly. The past results described above turned on the particular circumstances of those cases and are not a guarantee that a similar outcome will be achieved.

This article reflects the law as at August 2026.

About the author

Daisuke Matsumura, Attorney at Law
Dai-Ichi Tokyo Bar Association (registration no. 59077, admitted 2019)
Funado International Law Office (Fuse Building Main Wing 3F, 3-4-10 Takada, Toshima-ku, Tokyo)
Practice focused on criminal defence for foreign nationals and immigration proceedings.
Results include an acquittal in a Stimulants Control Act case (possession for the purpose of profit), non-prosecution in organised fraud cases, and special permission to stay in cases regarded as difficult.

Funado International Law Office
Website: https://matsumura-lawoffice.jp/
WeChat ID: matsumura1119